Emergence of two-level systems in glass formers: a kinetic Monte Carlo study

Abstract

Using a distinguishable-particle lattice model based on void-induced dynamics, we successfully reproduce the well-known linear relation between heat capacity and temperature at very low temperatures. The heat capacity is dominated by two-level systems formed due to the strong localization of voids to two neighboring sites, and can be exactly calculated in the limit of ultrastable glasses. Similar but weaker localization at higher temperatures accounts for the glass transition. The result supports the conventional two-level tunneling picture by revealing how two-level systems emerge from random particle interactions, which also cause the glass transition. Our approach provides a unified framework for relating microscopic dynamics of glasses at room and cryogenic temperatures.

References in corpus (3)

• Suppression of tunneling two-level systems in ultrastable glasses of indomethacin
• Direct evidence of void induced structural relaxations in colloidal glass formers
• Large heat-capacity jump in cooling-heating of fragile glass from kinetic Monte Carlo simulations based on a two-state picture

Cited by in corpus (5)

• Diffusion coefficient power laws and defect-driven glassy dynamics in swap acceleration
• Kauzmann Paradox: a crossover due to diminishing local excitations
• Surface mobility gradient and emergent facilitation in glassy films
• The distinguishable-particle lattice model of glasses in three dimensions
• A near-term quantum simulation of the transverse field Ising model hints at Glassy Dynamics